Spatial structure of peptides determined by residual dipolar couplings analysis.
The gated decoupled (13)C NMR spectra of a dipeptide (Glu-Trp) and a tetrapeptide (NAc-Ser-Phe-Val-Gly-OMe) were recorded in D(2)O and in a lyotropic alignment medium (pentaethylene glycol monododecyl ether/n-hexanol). The residual dipolar couplings were extracted as the differences between the observed couplings for the magnetic nuclei dissolved in the latter and former media. Using a computational optimization, the spatial structures of the compounds were calculated starting from their respective low energy conformations obtained on a semiempirical basis. The uniformity of each conformation was confirmed by the solid-state (13)C NMR spectra of powder samples. Differences between the starting structures and final ones, optimized when employing residual dipolar couplings, are discussed.
Klochkov
Vladimir V
VV
Department of Physics, Kazan State University, Kazan, Russian Federation.
Baikeev
Roustem F
RF
Skirda
Vladimir D
VD
Klochkov
Anton V
AV
Muhamadiev
Farhat R
FR
Baskyr
Igor
I
Berger
Stefan
S
D002247:Carbon Isotopes; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D015394:Molecular Structure; D010455:Peptides / Q000737:chemistry*
D002247:Carbon Isotopes; D010455:Peptides